包含头文件
原图
QImage image;
image.load("D:/1651966162841_Onue_.jpg");
ui->label->setPixmap(QPixmap::fromImage(image).scaled(ui->label->size()));

水平翻转
QImage image2;
image2 = image.mirrored(true,false);
ui->label->setPixmap(QPixmap::fromImage(image2).scaled(ui->label->size()));

垂直翻转
QImage image3;
image3 = image.mirrored(false,true);
ui->label->setPixmap(QPixmap::fromImage(image3).scaled(ui->label->size()));

顺时针/逆时针旋转
QImage image4;
QMatrix matrix;
matrix.rotate(30.0);//旋转角度,正数是顺时针负数是逆时针
image4 = image.transformed(matrix,Qt::FastTransformation);
ui->label->setPixmap(QPixmap::fromImage(image4).scaled(ui->label->size()));
